With recent efforts directed toward energy conservation along with the continuing escalation of fuel prices, the automotive industry has put an emphasis on increasing the fuel economy of vehicles that are put onto the road. Efforts to improve the fuel economy of vehicles have resided in improving the operation and efficiency of their engines, reducing the weight of their bodies and chassis, and improving the aerodynamic characteristics of their bodies. While great strides have been made in enhancing vehicle fuel economy as a result of improvements in these areas, there is still significant room for further advancement.
The impact of the wheels and their effect on vehicle aerodynamics as well as on vehicle fuel economy has been largely unappreciated. While there have been efforts to design and manufacture lighter weight wheels, such as through the removal of material from the spokes or the backsides of the wheel, the primary driver of these efforts has generally been cost considerations and not aerodynamics or fuel economy.
More recently, the potential aerodynamic impact of vehicle wheels themselves has been considered. These considerations have, however, largely ignored the fact that most wheel assemblies today employ covers or other structures over the wheel outboard surface that are designed to enhance the aesthetics of the wheel. Any aerodynamic benefit that may result from the design of the wheel alone is not maximized when a wheel cover or other aesthetic feature is secured to the outboard surface of the wheel that does not take into account the aerodynamics of the overall wheel assembly. Also, these claddings have been constructed to cover the entirety of the wheel exterior surface. This is done primarily for two main reasons. First, the aesthetic goal has been for a cladding to appear as an integral part of a wheel and having the cladding cover the entire wheel front surface has served that purpose. Second, vehicle wheel exterior surfaces are relatively unattractive from an aesthetic standpoint and it is thus desirable to cover the entirety of the wheel surface with the cladding. However, employing a full face cladding requires the use of additional material, which increases the total cost of the wheel assembly.
Additionally, attempts have been made to provide improved wheel aesthetics by attaching mechanical inserts to the wheel. These are generally undesirable as the attachment process can be labor intensive and expensive. Additionally, the inserts also have durability issues as can become easily detached from the wheel. Moreover, these attachments typically are configured as multiple different components that much each be separately attached to the wheel. Another attempt to improve wheel aesthetics involves painting the outboard wheel surface. Again, this process has limitations as it can be expensive and labor intensive.
Further, some vehicle wheels are configured such that any wheel cover or other aesthetic attachment would intrude upon curbside space, which would result in the wheel cover being bumped or damaged as a vehicle is being driven or parked.
It would thus be desirable to provide a wheel assembly that provides both improved aesthetics and improved wheel (and vehicle) aerodynamics.